stats final
using a normal curve table, if a person received a test score that is in the top 32% of all test scores, the person's z score must be at least
.46
in a distribution of z scores, the mean is always
0
when testing the significane of a correlation coefficiant, the usual null hypotheis is that the correlation in the population is...
0
if the mean score on a creativity test is 20, the standard deviation is 5, and the distribution is normal, the percentage of people who would obtain scores between 15 and 25 is
34%+34%=68%
the sum of squared deviations from the mean for a sample is 12, and there are 4 participants. the estimated population variance is..
4
rejecting the null hypothesis when the research hypothesis is false is
a type 1 error
failing to reject the null hypothesis when the research hypothesis is true is
a type 2 error
if an organizational psychologist conducts extensive interviews with 40 workers at a large factory to examine the morale among workers in general at that factory, the population is,
all the workers in the factory
as the number of people in a sample gets larger, the distribution of means
becomes a better approximation of the normal curve
to find the score in a t table at which the null hypothesis will be rejected, an experimenter must know the significance level, the degrees of freedom, and
cut off z score
which statement most completely describes the meaning of these numbers? (white-collar)
laborers are less satisfied than white-collar workers, and most laborers are about equally dissatisfied, while there is more variation in the satisfaction of white-collar workers
which statement is only true for the t test for depenedent means rather than t tests in general?
pretest-postest experimental designs are common
in principal, a distribution of means can be formed by
randomly taking a very large number of samples from a population, each of the same size, and making a distribution of their means
the... is, approximately, the average that a score differs from the mean
standard deviation
if an organizational psychologist conducts extensive interviews with 40 workers at a large factory to examine the morale among workers in general at that factory, the sample is,
the 40 workers interviewed
effect size is
the degree to which an experiemental manipulation seperates two populations
if an experimenter coducts a t test for indepenedt means and rejects the null hyp, the correct interpretation is that
the mean of one sample is so far formt eh mean of the other sample that the samples must come from populations with difference means
a child psychologist conducts a study to test whether infants born prematurely begin to walk earlier than do infants in general. which of the following scenerios represents a type 1 error
the psychologist concludes that premature infants do walk earlier than infants in general when the true situation is that they actually do no
the mean of a distribution of means is
the same as the original population mean
dividing the variance of the population of individuals by the number of individuals in each sample yields
the variance of the distribution means
o^2M represents
the variance of the distribution of means
if a psychologist tests whether there is any difference between how fast people work in the morning versus how fast they work in the evening, the null hyp is that
there is no difference in the speed at which people work
the mean, median, and mode will be the same when the distribution is...
unimodal and symmetrical
the formula for changing a z score to a raw score is
x=(z)(SD) + M
the formula for changing a raw score to a z score is
z=x-m/SD